const { src, dest, parallel, series, watch } = require('gulp')
const loadPlugins = require('gulp-load-plugins')
const plugins = loadPlugins()
const del = require('del')
const browserSync = require('browser-sync')
const bs = browserSync.create()

const clean = () => {
    return del(['dist', 'temp'])
}

const style = () => {
    return src('src/assets/styles/*.scss', { base: 'src' })
        .pipe(plugins.sass({ outputStyle: 'expanded' }))
        .pipe(dest('temp'))
        .pipe(bs.reload({ stream: true }))
}

const script = () => {
    return src('src/assets/scripts/*.js', { base: 'src' })
        .pipe(plugins.babel({ presets: ['@babel/preset-env'] }))
        .pipe(dest('temp'))
        .pipe(bs.reload({ stream: true }))
}

const page = () => {
    return src('src/*.html', { base: 'src' })
        .pipe(plugins.swig())
        .pipe(dest('temp'))
        .pipe(bs.reload({ stream: true }))
}

const image = () => {
    return src('src/assets/images/**', { base: 'src' })
        .pipe(plugins.imagemin())
        .pipe(dest('dist'))
}

const font = () => {
    return src('src/assets/font/**', { base: 'src' })
        .pipe(plugins.imagemin())
        .pipe(dest('dist'))
}

const extra = () => {
    return src('public/**', { base: 'public' })
        .pipe(dest('dist'))
}

const serve = () => {
    watch('src/assets/styles/*.scss', style)
    watch('src/assets/scripts/*.js', script)
    watch('src/*.html', page)

    watch([
        'src/assets/images/**',
        'src/assets/fonts/**',
        'public/**'
    ], bs.reload)
    
    bs.init({
        notify: false,
        port: 2080,
        // 监视变化的路径
        // files: 'dist/**',
        server: {
            baseDir: ['temp', 'src', 'public'],
            routes: {
                '/node_modules': 'node_modules'
            }
        }
    })
}

const useref = () => {
    return src('temp/*.html', { base: 'temp' })
        .pipe(plugins.useref({ searchPath: ['temp', '.'] }))
        .pipe(plugins.if(/\.js$/, plugins.uglify()))
        .pipe(plugins.if(/\.css$/, plugins.cleanCss()))
        .pipe(plugins.if(/\.html$/, plugins.htmlmin({
            collapseWhitespace: true,
            minifyCSS: true,
            minifyJS: true
        })))
        .pipe(dest('dist'))
}

const compile = parallel(style, script, page)

const build = series(clean, parallel(series(compile, useref), image, font, extra))

const develop = series(compile, serve)

module.exports = {
    clean,
    build,
    develop
}